振荡提取-高效液相色谱-电感耦合等离子体质谱法测定藻类中6种形态砷化合物

Arsenic Speciation Analysis of Algae by Using Vibrated Extraction High Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry

建立一种同时测定藻类中6种形态砷化合物(亚砷酸根、砷酸根、一甲基砷酸、二甲基砷酸、砷甜菜碱、砷胆碱)的振荡提取-高效液相色谱-电感耦合等离子体质谱(high performance liquid chromatography-inductively coupled plasma mass spectrometry,HPLC-ICPMS)分析方法。选取0.3 mol/L乙酸溶液作为提取剂,振荡提取藻类样品中的砷化合物,选用阴离子交换柱,25 mmol/L磷酸二氢铵和水作为流动相进行梯度洗脱,经HPLC-ICP-MS进行分离和定量分析。结果表明,在优化实验条件下,6种形态砷化合物在0～50范围内线性良好,相关系数均在0.9960以上,检出限为0.24～0.34μg/L,相对标准偏差为3.00%～3.70%,加标回收率在之间85.1%～98.3%。4种处理方式后的藻类样品的测定结果显示,有机砷是主要的砷化物,占总砷含量的92.34%。方法灵敏度高,前处理简单高效,可以有效地分析藻类样品中不同形态的砷化物。

The speciation of arsenic in algae was analyzed using vibrated extraction combined with high performance liquid chromatography - inductively coupled plasma mass spectrometry, HPLC - ICP - MS. Six arsenic compounds were extracted from the samples using 0. 3 mol/L acetic acid solution as extraction solvent. The chromatographic separation was performed on a hanfiton PRP- X100 anion exchange eolunm using a nfixture of 25 mmol/L amnloniunl dihydrogen phosphate and water as the mobile phase. Under the optinfized conditions, there were good linear relationships in the range of 0 -50μg/L for six arsenic species （ AsC, AsB, As III, DMA, MMA and As V ） were between 0.24 and 0.34 μg/L, the precision of the method, expressed as relative standard deviation（RSD） ,was less than 5%. The recoveries of AsC,AsB,As III, DMA,MMA and As V were in the range of 85.1% -98.3%. Speeiation analysis could accurately determine six arsenic species in algae. Organic arsenic was the main species in algae,which was in the range of 80.48% ~ 99%. this method was simple,rapid, sensitive and accurate, and could meet the requirements for the quantitative analysis of arsenic speeiation in algae.